Jeudi
03/05/2018
11h

Salle Amphi Pasteur

Dr. Roméo RICCI (Institut de génétique et de biologie moléculaire et cellulaireIllkirch-Graffenstaden)

contact : benedicte.py@inserm.fr

The inflammasome is a multiprotein complex that senses tissue damage and infectious agents to initiate immune responses. Distinct inflammasomes containing specific sensing molecules, including NLRP3, exist. We discovered that assembly of the NLRP3 inflammasome requires recruitment of NLRP3 to mitochondria-associated Endoplasmic Reticulum (ER) membranes (MAMs) adjacent to Golgi membranes. Compartmentalization of NLRP3 to MAMs is crucial for its self-oligomerization, while signaling from the Golgi is required to release NLRP3 from MAMs resulting in full assembly of the inflammasome. Our work thus provided unique insights into the spatially and temporally controlled mechanisms underlying NLRP3 inflammasome assembly.

Lundi
14/05/2018
11h00

Salle de SdT CRC

Olivier POURQUIÉ  (Harvard Medical School)

Vendredi
18/05/2018
11h00

Salle SdT CRC

Jane MELLOR (University of Oxford)

Jeudi
24/05/2018
11h00

Salle SdT CRC

Florent GINHOUX (Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (A*STAR). Singapore)                     

contact : fl.cosset@ens-lyon.fr

Dendritic cells (DCs) are professional antigen-presenting cells that mediate immune responses. Important questions on the origins and differentiation paths of human DC populations remain unanswered. First, we combined two high-dimension techniques, single-cell mRNA sequencing and Cytometry by Time of Flight mass spectrometry to define and characterize human DC precursors (pre-DC) present in adult bone marrow and blood and revealed that pre-DC comprises distinct lineage-committed sub-populations. We also characterized the human fetal DC lineage and show that similar DC subpopulations can be identified in fetal tissues and are related to adult populations. However, fetal DC strongly promoted regulatory T-cell induction and inhibiting T-cell tumour-necrosis factor-α production through arginase-2 activity, indicating that they mediate homeostatic immune-suppressive responses during gestation. Altogether, we show that the DC lineage shares common development pathways from early fetal development to adulthood. However, DC functions differ drastically depending on the environment in which they are immersed.

Vendredi 25/05/2018
11h

Salle SdT CRC

David LLERES  (IGMM)

Mardi
29/05/2018
9h30

Salle de réunion IVPC

Jeudi 31/05/2018
11h

Salle Sdt CRC

Thomas PIETSCHMANN (TWINCORE - Zentrum für Experimentelle und Klinische Infektionsforschung GmbH. Hannover,Germany)                 

contact : fl.cosset@ens-lyon.fr

HCV infection affects ca. 71 million individuals worldwide. These patients are at risk to develop severe liver disease including cirrhosis and liver cancer. Novel therapies have been licensed and HCV infection can be cured. However, these therapies are expensive, many HCV infected patients are not diagnosed, and treatment-induced viral clearance does not protect from HCV re-infection. Therefore, development of a prophylactic vaccine is an important clinical need. Unfortunately, immunocompetent animal models are lacking so that analysis of protective immunity against HCV, and prioritization of vaccine candidates is difficult. HCV has a narrow species tropism and naturally infects only humans. The viral and host determinants governing HCV species tropism are incompletely defined. We used genome-wide cDNA screens and iterative virus selection and adaptation approaches to dissect viral and host factors that define the mechanisms of HCV species tropism. Using these approaches we identified two mouse factors  constitutively expressed in mouse livers that restrict HCV infection. Moreover, viral variants with extended species tropism were developed and characterized. Ultimately, this work should facilitate development of animal models for HCV vaccine research.